The present invention relates to the production of 1,3-diols and/or 3-hydroxyaldehydes thereof from epoxides. More particularly, the invention relates to hydroformylation catalysts, processes for making hydroformylation catalysts and processes using hydroformylation catalysts for producing such 1-3 diols and/or 3 -hydroxyaldehydes from epoxides.
Glycols in general are valuable chemical compounds which find a wide variety of utilities. Such compounds are used, for example, as chemical intermediates in the manufacture of esters, as well as in the synthesis of polyesters. 1,3-Propanediol, in particular, had been found to be especially useful in a number of applications. 1,3-Propanediol has been prepared by acid-catalyzed hydration of acrolein to form 3-hydroxypropanal which is subsequently hydrogenated to the corresponding glycol. Because of the relatively low reaction rates and low product yields obtained, this approach has not led to a viable process for making 1,3-propanediol in large commercial quantities.
The preparation of 1,3-diols, i.e., 1,3-glycols, by the hydroformylation of epoxides, utilizing phosphine-modified cobalt carbonyl complexes as the catalyst, is disclosed in Smith et al U.S. Pat. No. 3,463,819. In particular, this patent shows the production of 1,3-propanediol by hydroformylation of ethylene oxide, using a tertiary phosphine-modified cobalt carbonyl catalyst. Very high cobalt-containing catalyst concentrations are needed to provide good yields of 1,3-propanediol.
Lawrence et al U.S. Pat. No. 3,687,981 discloses a process for manufacturing 1,3-propanediol which employs two separate stages. In the first stage, ethylene oxide undergoes a hydroformylation reaction in the presence of a hydroformylation catalyst containing a transition metal, particularly metals of Group VIII of the periodic chart, e.g., cobalt carbonyl tertiary phosphine and rhodium carbonyl, to produce 2-(2 hydroxyethyl)-4-hydroxy-1,3-dioxane. The dioxane compound, together with a small amount of 3-hydroxypropionaldehyde, is catalytically hydrogenated to form 1,3- propanediol.
Smith et al U.S. Pat. No. 3,456,017 discloses production of 1,3-propanediol by hydroformylation of ethylene oxide using, as catalyst, dicobalt hexacarbonyl complexes wherein the remaining two coordination sites of the cobalt moieties are complexed with one or more tertiary phosphine ligands.
Horvitz et al U.S. Pat. No. 4,322,355 discloses the reaction of olefin with aldehyde in the presence of a strong acid catalyst and a co-catalyst selected from antimony and bismuth oxides and salts to provide one, or a mixture of, 1,3-difunctional compounds.
European Patent Publication No. 0257967 discloses a process for producing 1,3-glycols by reacting an epoxide with synthesis gas in an acidic medium in the presence of rhodium and a phosphine. This publication discloses a reaction mixture containing (1) the epoxide: (2) rhodium; (3) a phosphine; (4) water; (5) carbon monoxide; (6) hydrogen; and (7) an acid. Although a wide range of acid to rhodium molar ratios is disclosed, e.g., from 10/1 to 1/10, this publication discloses a preference for a molar ratio of acid to rhodium of approximately 1. This publication discloses that an induction period, of about 0.5 to 1 hour or more in duration, occurs after the reaction mixture is formed before gas uptake begins. This "induction period", which itself is wasteful because a larger reactor and/or longer time is required to produce a given amount of 1,3-diol, is in part a result of combining some of the epoxide with the rhodium and phosphine, and possibly other components, to produce the true hydroformylation catalyst. Thus, some of the epoxide is incorporated into the hydroformylation catalyst. Using the epoxide to produce the catalyst reduces the ultimate yield, of desired products, e.g., 1,3-diol. A rhodium-containing catalyst which does not require an induction period and/or which is made without incorporation of epoxide would clearly be advantageous.
Murphy et al U.S. Pat. No. 4,873,378 discloses substantially the same process as that disclosed in the above-noted European Patent Publication. In addition, this patent discloses that a salt having an alkali metal cation and a solubilizing anion is also present in the reaction mixture. This patent discloses that the "induction period" is eliminated in certain examples containing relatively large amounts of alkali metal salts. No salts other than alkali metal salts are suggested.
Murphy et al U.S. Pat. No. 4,873,379 discloses a process for producing 1,3-diols. This patent discloses a reaction mixture containing (1) an epoxide; (2) rhodium; (3) an alkali metal salt promotor; (4) water; (5) carbon monoxide; and (6) hydrogen. No promotors other than alkali metal salts are suggested.
European Patent Publication No. 0306094 discloses a process for the hydroformylation of certain acrylic acid derivatives in the presence of a homogeneous catalyst system comprising a rhodium compound and one or more triphenylphosphites. No epoxide hydroformylation is suggested.
There continues to be a need for a new epoxide hydroformylation catalyst, and for processes for making and using the same, particularly to produce 1,3-diols and/or 3-hydroxyaldehydes.